How can I solve the N-Queens problem using different programming languages?

How can I solve the N-Queens problem using different programming languages?

You can solve the N-Queens problem using various programming languages like Python, Java, and C++. Would you like examples in a specific language?

Yes, please show me how to do it in Python.

Sure! Here's a simple backtracking solution in Python:

def solve_n_queens(n):
    def is_safe(board, row, col):
        for i in range(col):
            if board[row][i] == 1:
                return False
        for i, j in zip(range(row, -1, -1), range(col, -1, -1)):
            if board[i][j] == 1:
                return False
        for i, j in zip(range(row, n, 1), range(col, -1, -1)):
            if board[i][j] == 1:
                return False
        return True

    def solve_util(board, col):
        if col >= n:
            return True
        for i in range(n):
            if is_safe(board, i, col):
                board[i][col] = 1
                if solve_util(board, col + 1):
                    return True
                board[i][col] = 0
        return False

    board = [[0] * n for _ in range(n)]
    if not solve_util(board, 0):
        return "No solution exists"
    return board

print(solve_n_queens(4))

That's great! Can you provide a Java example as well?

Absolutely! Here's a Java implementation of the N-Queens problem:

public class NQueens {
    static int N = 4;

    static boolean isSafe(int board[][], int row, int col) {
        for (int i = 0; i < col; i++)
            if (board[row][i] == 1)
                return false;
        for (int i = row, j = col; i >= 0 && j >= 0; i--, j--)
            if (board[i][j] == 1)
                return false;
        for (int i = row, j = col; j >= 0 && i < N; i++, j--)
            if (board[i][j] == 1)
                return false;
        return true;
    }

    static boolean solveNQUtil(int board[][], int col) {
        if (col >= N)
            return true;
        for (int i = 0; i < N; i++) {
            if (isSafe(board, i, col)) {
                board[i][col] = 1;
                if (solveNQUtil(board, col + 1))
                    return true;
                board[i][col] = 0;
            }
        }
        return false;
    }

    static void solveNQ() {
        int board[][] = new int[N][N];
        if (!solveNQUtil(board, 0)) {
            System.out.print("Solution does not exist");
            return;
        }
        printSolution(board);
    }

    static void printSolution(int board[][]) {
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++)
                System.out.print(" " + board[i][j] + " ");
            System.out.println();
        }
    }

    public static void main(String args[]) {
        solveNQ();
    }
}